Comparison of Supraclavicular Brachial Plexus Block and Local Anaesthetic Infiltration in Arteriovenous Fistula Surgeries

Abstract

Introduction: Surgical construction of an arteriovenous fistula (AVF) is the most common procedure performed to gain access for hemodialysis in patients with end stage renal disease. With over 30% failure rate in arteriovenous fistula surgeries performed under local anaesthesia, brachial plexus block (BPB) is preferred as it improves the duplex sonography parameters, which may reduce the failure rate. However, the studies on the role of brachial plexus block in improving the AVF outcome are limited. We, therefore, evaluated the effectiveness of ultrasound guided brachial plexus block against the traditional local infiltration (LI) in AV fistula surgeries.Methods: 200 patients were randomly allocated to receive either Local Infiltration; Group I (LI-G) at the surgical site or supraclavicular brachial plexus block; Group II (BPB-G). The Doppler assessment of vessels was done before and after the block, at fixed time intervals and compared between the two groups. Intergroup comparison was also done with respect to the need for supplemental analgesics intraoperatively and the duration of postoperative analgesia. All the surgeries were performed by the same anesthetist and the surgeon.Results: The primary patency rates at three months were 100 percent in the brachial plexus block group versus 95 percent in the local infiltration group. The difference, however, was not significant statistically. Post anaesthesia, the brachial artery diameter was increased significantly in the BPB group vs LI group (mean difference [MD], 0.11; 95 % confidence interval [CI]: 0.00-0.22; p value 0.03). There was significant increase in radial artery flow in BPB group than the LI group (MD, 8.27; 95 % CI: -9.83 - -6.85; p value <0.001). The brachial plexus block significantly enhanced the duration of perioperative analgesia (MD, -339.35; 95 % CI: -349.02 - -329.68; p value <0.001) with minimal need for supplementary intravenous (IV) analgesics. Conclusion: When used for arteriovenous fistula access surgeries, supraclavicular brachial plexus block significantly improves the arteriovenous fistula flow characteristics as compared with local infiltration and provides additional advantage of pain relief and temporary sympathectomy.